Gibson Nut Shape

Hey Everybody!

I have a question about the shape of Gibson nuts, specifically Les Pauls. Generally, I see a shape that is a rectangle with rounded edges on the top, and a approximately 10° angle on the top. I have a '77 Les Paul on the bench that needs a new nut. The existing nut looks different than what I am used to seeing. It is has a rounder shape on the tops and sides. How long has Gibson been using their current nut shape? Is this a correct shape for the era? Thanks, Cyrus